Proper axle-to-axle distance varies from bow to bow. Manufacturer specification for the bow above is 40 inches.
Photos provided by Bill Marchel ,
Archers can test their bows by shooting paper targets at close range. Properly tuned bows will leave perfectly round holes.
How to ... fine-tune your bow for optimal performance
- Article by: Bill Marchel
- Special to the Star Tribune
- July 19, 2013 - 8:48 AM
Brainerd, Minn. – Confidence is huge in most undertakings. This is especially true for the hunting archer. A close-range shot at, say, a big whitetail buck is especially unnerving. This is compounded if, well … your compound bow is out of shape.
If you haven’t had your bow-and-arrow combination looked at by an archery professional, late summer is the best time to do it. Minnesota’s archery deer season is only two months away.
So, that’s just what I did last week.
“The first thing we do is to check the bow for cracks or stress fractures,” said Scott Thesing, manager and pro staff technician at Archery Country in Brainerd. “We don’t want to get hurt, or have the bow blow up on somebody.”
After Thesing gave my bow the once over, he proceeded to check a few critical measurements. First he measured the axle-to-axle length. Then he checked the timing marks and brace height. These dimensions are specific to each manufacturer and bow model. The measurements on my bow were right on. Had my bow string or cables been stretched or worn, the problem would have shown up during the measurement process.
Next he checked for cam lean. Without getting too technical, a bow that displays cam lean generally has a problem with the Y-cables. My bow showed no cam lean.
“If a person shoots a lot, he or she should replace the string and cables on their bows once a year,” said Thesing. “Otherwise, every other year is fine.” I had my string and cables replaced late last summer.
Now it was time to actually shoot an arrow. Thesing performed what is called the “paper test.” He shot my bow-and-arrow combination several times through a sheet of paper placed at very close range, roughly three feet. This test not only determines whether my bow and arrow has the correct combination of draw weight, arrow length and arrow spine, it also determines whether there are problems with the placement of the arrow rest (on the bow) or the nocking point (on the bowstring).
Ideally, the arrow should penetrate the paper leaving a perfectly round hole. An elongated tear in any direction shows there is a problem. Adjustments can be made in several ways. If the arrow’s spine (or its stiffness) is too great or too light, an arrow with a different spine can be used. If the arrow’s spine is correct, then an adjustment of the arrow rest or nock point is in order.
My arrows were on the stiff side for my bow’s draw weight, a fact that revealed itself with a slightly elongated hole. Thesing tried an arrow with a different spine weight and was able to shoot perfect holes.
So, I left Archery Country with a dozen new arrows and a slightly thinner wallet. What’s important, though, is that I now know my bow and arrow combination are performing top-notch.
This fall, when, hopefully, I draw on that big whitetail buck, I’ll have complete confidence in my bowhunting equipment.
The rest will be up to me.
Bill Marchel, an outdoor writer and photographer, lives near Brainerd.
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